Next.js 9.1.7 Impossible to test next/link with enzyme mount.

Bug report

Impossible to test next/link with enzyme mount.

Describe the bug

When trying to test a component with next/link using an enzyme mount, an error occurs

Error: Uncaught [TypeError: Cannot read property 'pageLoader' of null].

The error is only in version 9.1.7, in previous versions everything was fine.

To Reproduce

repository to reproduce https://github.com/gudvinga/next-9.1.7-link-jest-enzyme

1. yarn install
2. yarn test
3. See error

Expected behavior

Should work without error.

System information

• Version of Next.js: 9.1.7

[Erazihel]

Got the same error using React Testing Library:

  ● Component › should render correctly

    TypeError: Cannot read property 'pageLoader' of null

       6 | describe("Component", () => {
       7 |   it("should render correctly", () => {
    >  8 |     const { getByText } = render(<Component />);
         |                           ^
       9 |
      10 |     expect(getByText("Hello World")).toBeDefined();
      11 |   });

      at Link.handleRef (packages/header/node_modules/next/dist/client/link.js:8:710)

Component.tsx:

...
            <Link href="/">
              <a className={styles.Link}>Hello World</a>
            </Link>
...

Using Next@9.1.6 does not throw that error.

[lednhatkhanh]

Facing exact same problem with @testing-library/react